Vein of
Galen Aneurysm Neonates
with aneurysm of the vein of Galen may be macrocephalic at birth. Nevertheless,
the most common neonatal presentations of vein of Galen aneurysm in the
neonatal period are cardiac failure (Figure 289.1[A]), cerebral infarction,
or cerebral bleed. The cause of cardiac failure is multifactorial. High
cardiac output due to decreased cerebrovascular resistance, increased
venous return, and cardiac ischemia due to decreased diastolic pressure
contribute to the production of cardiac failure. Macrocephaly can be caused
by the large size of the vein of Galen aneurysm, but most often it is
caused by an obstruction of the aqueduct of Sylvius. A cranial bruit is
often present in neonates with vein of Galen aneurysm. Vein
of Galen aneurysm is a malformation due to abnormal connections between
intracranial vessels (usually thalamoperforators, choroidal, and anterior
cerebral arteries), and a vein in the region of the vein of Galen (may
not be the vein of Galen but a persistent fetal structure, the midline
prosencephalic vein). Vein of Galen aneurysm is diagnosed by contrast-enhanced
CT, MRI, or angiogram of the brain (Figure 289.1[B and C]).